中文摘要：

通过对3根钢骨-方钢管高强混凝土柱按ISO834标准曲线升温作用后进行轴压承载力试验,探究均匀受火后以及不均匀受火后钢骨-方钢管混凝土柱的轴压力学性能。试验结果表明：相同条件下内置钢骨的方钢管混凝土柱承载力损伤程度要小于钢管混凝土柱;与钢骨-方钢管混凝土柱在均匀受火后相比,不均匀受火后试件的承载力损失程度较轻。同时在确定高温作用后钢材以及混凝土应力-应变关系的基础上,利用数值方法得出火灾作用后轴压构件轴压-应变关系曲线,试验结果验证了理论分析结果的正确性。并利用理论模型分析配骨指标、套箍指标等因素对构件火灾后钢骨-方钢管混凝土柱轴压承载力的影响,分析结果表明受火时间、截面边长以及配骨指标都对火灾后构件轴压承载力的影响较大。

英文摘要：

To study the behavior of square steel tube short columns with steel reinforced concrete（ STSRC）,three specimens were tested after exposure to standard fire of ISO834. The test results showed that STSRC lost more strength in uniform fire than in non-uniform fire; the damage degree of STSRC was lighter than concrete filled steel tube columns under the same circumstance. Based on material＇s constitutive model,a method was developed to calculate the load-strain curve of the specimens. The analysis model was verified through test data. The model was also used to analyse the influencing parameters of STSRC after fire. The analytic result showed that the cross size,reinforcing steel index and the time for exposure to fire had a greater effect on the axial compressive bearing capacity.